Introduce a generic helper function that can set a MAC address using data from the OMAP unique CPU ID register. For comparison purposes this produces a MAC address of 2e:40:70:f0:12:06 for the ethernet device on my Panda. Note that this patch requires the fix patch for CPU ID register indexes previously posted to linux-omap, otherwise the CPU ID is misread on Panda by the existing function to do it. This patch is already on linux-omap. "OMAP2+:Common CPU DIE ID reading code reads wrong registers for OMAP4430" http://git.kernel.org/?p=linux/kernel/git/tmlind/linux-omap-2.6.git;a=commit;h=b235e007831dbf57710e59cd4a120e2f374eecb9 Signed-off-by: Andy Green <andy.green@xxxxxxxxxx> --- arch/arm/mach-omap2/id.c | 39 +++++++++++++++++++++++++++++++++ arch/arm/mach-omap2/include/mach/id.h | 1 + 2 files changed, 40 insertions(+), 0 deletions(-) diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c index 2537090..e46b430 100644 --- a/arch/arm/mach-omap2/id.c +++ b/arch/arm/mach-omap2/id.c @@ -557,3 +557,42 @@ void __init omap2_set_globals_tap(struct omap_globals *omap2_globals) else tap_prod_id = 0x0208; } + +/* + * this uses the unique per-cpu info from the cpu fuses set at factory to + * generate a 6-byte MAC address. Two bits in the generated code are used + * to elaborate the generated address into four, so it can be used on multiple + * network interfaces. + */ + +void omap2_die_id_to_ethernet_mac(u8 *mac, int subtype) +{ + struct omap_die_id odi; + u32 tap = read_tap_reg(OMAP_TAP_IDCODE); + + omap_get_die_id(&odi); + + mac[0] = odi.id_2; + mac[1] = odi.id_2 >> 8; + mac[2] = odi.id_1; + mac[3] = odi.id_1 >> 8; + mac[4] = odi.id_1 >> 16; + mac[5] = odi.id_1 >> 24; + + /* XOR other chip-specific data with ID */ + + tap ^= odi.id_3; + + mac[0] ^= tap; + mac[1] ^= tap >> 8; + mac[2] ^= tap >> 16; + mac[3] ^= tap >> 24; + + /* allow four MACs from this same basic data */ + + mac[1] = (mac[1] & ~0xc0) | ((subtype & 3) << 6); + + /* mark it as not multicast and outside official 80211 MAC namespace */ + + mac[0] = (mac[0] & ~1) | 2; +} diff --git a/arch/arm/mach-omap2/include/mach/id.h b/arch/arm/mach-omap2/include/mach/id.h index 02ed3aa..373313a 100644 --- a/arch/arm/mach-omap2/include/mach/id.h +++ b/arch/arm/mach-omap2/include/mach/id.h @@ -18,5 +18,6 @@ struct omap_die_id { }; void omap_get_die_id(struct omap_die_id *odi); +void omap2_die_id_to_ethernet_mac(u8 *mac, int subtype); #endif -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
